Method and apparatus for robust information coding

- Digimarc Corporation

A digital signal is imperceptibly embedded into an input source signal, such as an image or video signal, to produce an encoded (sometimes termed "watermarked") signal. The principle of quasi-rotational symmetry is employed to facilitate detection of the embedded signal notwithstanding rotation of the encoded signal. Single or multiple degrees of symmetry can be employed. In another aspect, the digital signal is transformed to a frequency domain and phase-only filtered prior to its combination with the input source signal. In an illustrative embodiment, this filtering operation helps hide the digital signal within the source signal, and facilitates detection of the embedded digital signal even after the encoded signal has undergone various forms of corruption.

Skip to:  ·  Claims  ·  References Cited  · Patent History  ·  Patent History

Claims

1. In a method of steganographically processing an image signal to embed multi-bit information therein, an improvement comprising representing said information in the form of a plurality of partially overlapping quasi-rotationally symmetric patterns, and processing the image signal to imperceptibly enabled said plurality of partially overlapping quasi-rotationally symmetric patterns therein, wherein said quasi-rotational symmetry of the patterns facilitates detection of the multi-bit information from a resulting processed image signal if said processed image signal is corrupted by scaling or rotation operations.

2. The method of claim 1 in which each of said quasi-rotationally symmetric patterns encodes a single bit of information.

3. The method of claim 1 in which said plurality of quasi-rotationally symmetric patterns comprises at least four patterns, and centers of said plurality of patterns lie on a circle, thereby forming a rosette of patterns.

4. The method of claim 3 which includes processing the image signal to encode a plurality of said rosettes therein, wherein the rosettes are spaced across a representation of the image signal in a pixel domain so that a pattern of one rosette overlaps a pattern of another rosette.

5. The method of claim 4 in which patterns of one rosette overlap patterns of six other rosettes.

6. The method of claim 3 which includes providing at least one pattern in said rosette with a distinguishing feature to aid in distinguishing it from other pattern in said rosette during decoding.

7. The method of claim 1 which includes pre-processing the plurality of patterns prior to encoding the image signal therewith, said pre-processing including performing a fourier transform on said plurality of patterns to produce transformed data, and applying a filtering function to said transformed data.

8. The method of claim 7 in which the filtering function is rotationally symmetric within a spatial frequency domain.

9. The method of claim 7 in which the filtering function is phase-only.

10. The method of claim 1, further comprising storing the processed image signal on a physical medium.

11. The method of claim 10, wherein the physical medium comprises paper.

12. The method of claim 10, wherein the physical medium comprises a magnetic or electronic storage medium.

13. The method of claim 1 in which said patterns are wave patterns.

14. The method of claim 1 in which said quasi-rotationally symmetric patterns exhibit symmetry about more than one axis.

15. The method of claim 1 in which said quasi-rotationally symmetric patterns exhibit symmetry about more than two axes.

16. The method of claim 1 in which said image signal is represented as pixel data in a spatial image domain.

17. The method of claim 16 in which said processing includes adding a bit-mapped representation of said patterns to said pixel data.

18. The method of claim 1 in which the patterns exhibit said quasi-rotational symmetry when represented as pixel data in a spatial image domain.

19. The method of claim 1 in which the quasi-rotational symmetry of the patterns facilitates detection of the multi-bit information from the processed image signal if the processed image signal is corrupted by a rotation operation.

20. The method of claim 1 in which the quasi-rotational symmetry of the patterns facilitates detection of the multi-bit information from the processed image signal if the processed image signal is corrupted by a scaling operation.

21. The method of claim 1 in which the quasi-rotational symmetry of the patterns facilitates detection of the multi-bit information from the processed image signal by enabling re-registration of a corrupted, processed image signal by reference to said patterns.

22. A computer storage medium having instructions stored therein for causing a computer to perform the method of claim 1.

23. In a computer-implemented method of producing a steganographically encoded signal, the method including storing a representation of an input signal in a memory, and combining a multi-bit data signal with said input signal, the method being practiced using a programmed processor in conjunction with said memory, an improvement comprising:

transforming the multi-bit data signal to produce a transformed signal in a complementary frequency domain;
applying a phase-only filtering function to the transformed signal to produce a filtered signal; and
combining the filtered signal with the representation of the input signal to effect steganographic encoding thereof, wherein the multi-bit data signal is hidden within the first signal without commercially impairing the value thereof.

24. The method of claim 23 in which the input signal is a set of image data represented as pixel data in a spatial image domain, and in which the multi-bit data signal comprises data corresponding to a plurality of quasi-rotationally symmetric patterns.

25. The method of claim 23 in which the combining step comprises adding the filtered signal to the representation of the input signal.

26. The method of claim 23 which includes representing the filtered signal as a group of pixels prior to combining same with the representation of the input signal.

27. A computer storage medium having instructions stored therein for causing said computer to perform the method of claim 23.

Referenced Cited

U.S. Patent Documents

3493674 February 1970 Houghton
3569619 March 1971 Simjian
3585290 June 1971 Sanford
3665162 May 1972 Yamamoto et al.
3703628 November 1972 Philipson, Jr.
3805238 April 1974 Rothfjell
3809806 May 1974 Walker et al.
3838444 September 1974 Loughlin et al.
3914877 October 1975 Hines
3922074 November 1975 Ikegami et al.
3971917 July 27, 1976 Maddox et al.
3982064 September 21, 1976 Barnaby
3984624 October 5, 1976 Waggener
4025851 May 24, 1977 Haselwood et al.
4225967 September 30, 1980 Miwa et al.
4230990 October 28, 1980 Lert, Jr. et al.
4231113 October 28, 1980 Blasbalg
4238849 December 9, 1980 Gassmann
4252995 February 24, 1981 Schmidt et al.
4313197 January 26, 1982 Maxemchuk
4367488 January 4, 1983 Leventer et al.
4379947 April 12, 1983 Warner
4380027 April 12, 1983 Leventer et al.
4389671 June 21, 1983 Posner et al.
4395600 July 26, 1983 Lundy et al.
4423415 December 27, 1983 Goldman
4425642 January 10, 1984 Moses et al.
4476468 October 9, 1984 Goldman
4528588 July 9, 1985 Lofberg
4532508 July 30, 1985 Ruell
4547804 October 15, 1985 Greenberg
4553261 November 12, 1985 Froessl
4590366 May 20, 1986 Rothfjell
4595950 June 17, 1986 Lofberg
4637051 January 13, 1987 Clark
4639779 January 27, 1987 Greenberg
4647974 March 3, 1987 Butler et al.
4654867 March 31, 1987 Labedz et al.
4660221 April 21, 1987 Dlugos
4663518 May 5, 1987 Borror et al.
4665431 May 12, 1987 Cooper
4672605 June 9, 1987 Hustig et al.
4675746 June 23, 1987 Tetrick et al.
4677435 June 30, 1987 Causse D'Agraives
4682794 July 28, 1987 Margolin
4703476 October 27, 1987 Howard
4712103 December 8, 1987 Gotanda
4718106 January 5, 1988 Weinblatt
4739377 April 19, 1988 Allen
4750173 June 7, 1988 Bluthgen
4765656 August 23, 1988 Becker et al.
4775901 October 4, 1988 Nakano
4776013 October 4, 1988 Kafri et al.
4805020 February 14, 1989 Greenberg
4807031 February 21, 1989 Broughton et al.
4811357 March 7, 1989 Betts et al.
4811408 March 7, 1989 Goldman
4820912 April 11, 1989 Samyn
4835517 May 30, 1989 van der Gracht et al.
4855827 August 8, 1989 Best
4864618 September 5, 1989 Wright et al.
4866771 September 12, 1989 Bain
4874936 October 17, 1989 Chanduer et al.
4876617 October 24, 1989 Best et al.
4879747 November 7, 1989 Leighton et al.
4884139 November 28, 1989 Pommier
4885632 December 5, 1989 Mabey et al.
4903301 February 20, 1990 Kondo et al.
4908836 March 13, 1990 Rushforth et al.
4908873 March 13, 1990 Philibert et al.
4920503 April 24, 1990 Cook
4921278 May 1, 1990 Shiang et al.
4939515 July 3, 1990 Adelson
4941150 July 10, 1990 Iwasaki
4943973 July 24, 1990 Werner
4943976 July 24, 1990 Ishigaki
4944036 July 24, 1990 Hyatt
4963998 October 16, 1990 Maufe
4965827 October 23, 1990 McDonald
4967273 October 30, 1990 Greenberg
4969041 November 6, 1990 O'Grady et al.
4972471 November 20, 1990 Gross et al.
4972476 November 20, 1990 Nathans
4979210 December 18, 1990 Nagata et al.
4993068 February 12, 1991 Piosenka
4996530 February 26, 1991 Hilton
5010405 April 23, 1991 Schreiber et al.
5027401 June 25, 1991 Soltesz
5036513 July 30, 1991 Greenblatt
5063446 November 5, 1991 Gibson
5073899 December 17, 1991 Collier et al.
5075773 December 24, 1991 Pullen et al.
5077608 December 31, 1991 Dubner
5077795 December 31, 1991 Rourke et al.
5079648 January 7, 1992 Maufe
5095196 March 10, 1992 Miyata
5113437 May 12, 1992 Best et al.
5144660 September 1, 1992 Rose
5148498 September 15, 1992 Resnikoff et al.
5150409 September 22, 1992 Elsner
5161210 November 3, 1992 Druyvesteyn et al.
5166676 November 24, 1992 Milheiser
5181786 January 26, 1993 Hujink
5185736 February 9, 1993 Tyrrell
5199081 March 30, 1993 Saito et al.
5200822 April 6, 1993 Bronfin et al.
5212551 May 18, 1993 Conanan
5213337 May 25, 1993 Sherman
5228056 July 13, 1993 Schilling
5243423 September 7, 1993 DeJean et al.
5245329 September 14, 1993 Gokcebay
5247364 September 21, 1993 Banker et al.
5253078 October 12, 1993 Balkanski et al.
5257119 October 26, 1993 Funada et al.
5259025 November 2, 1993 Monroe et al.
5267334 November 30, 1993 Normille et al.
5280537 January 18, 1994 Sugiyama et al.
5293399 March 8, 1994 Hefti
5295203 March 15, 1994 Krause et al.
5299019 March 29, 1994 Pack et al.
5305400 April 19, 1994 Butera
5315098 May 24, 1994 Tow
5319453 June 7, 1994 Copriviza et al.
5319724 June 7, 1994 Blonstein et al.
5319735 June 7, 1994 Preuss et al.
5325167 June 28, 1994 Melen
5327237 July 5, 1994 Gerdes et al.
5337362 August 9, 1994 Gormish et al.
5351302 September 27, 1994 Leighton et al.
5379345 January 3, 1995 Greenberg
5387941 February 7, 1995 Montgomery et al.
5394274 February 28, 1995 Kahn
5396559 March 7, 1995 McGrew
5398283 March 14, 1995 Virga
5404160 April 4, 1995 Schober et al.
5404377 April 4, 1995 Moses
5408542 April 18, 1995 Callahan
5418853 May 23, 1995 Kanota et al.
5422963 June 6, 1995 Chen et al.
5422995 June 6, 1995 Aoki et al.
5425100 June 13, 1995 Thomas et al.
5428606 June 27, 1995 Moskowitz
5428607 June 27, 1995 Hiller et al.
5432542 July 11, 1995 Thibadeau et al.
5432870 July 11, 1995 Schwartz
5446273 August 29, 1995 Leslie
5450122 September 12, 1995 Keene
5450490 September 12, 1995 Jensen et al.
5461426 October 24, 1995 Limberg et al.
5469506 November 21, 1995 Berson et al.
5473631 December 5, 1995 Moses
5479168 December 26, 1995 Johnson et al.
5481294 January 2, 1996 Thomas et al.
5488664 January 30, 1996 Shamir
5499294 March 12, 1996 Friedman
5515081 May 7, 1996 Vasilik
5524933 June 11, 1996 Kunt et al.
5530759 June 25, 1996 Braudaway
5532920 July 2, 1996 Hartrick et al.
5539471 July 23, 1996 Myhrvold et al.
5539735 July 23, 1996 Moskowitz
5541662 July 30, 1996 Adams et al.
5541741 July 30, 1996 Suzuki
5557333 September 17, 1996 Jungo et al.
5559559 September 24, 1996 Jungo et al.
5568179 October 22, 1996 Diehl et al.
5568570 October 22, 1996 Rabbani
5572010 November 5, 1996 Petrie
5572247 November 5, 1996 Montgomery et al.
5576532 November 19, 1996 Hecht et al.
5579124 November 26, 1996 Aijala et al.
5587743 December 24, 1996 Montgomery
5606609 February 25, 1997 Houser et al.
5614940 March 25, 1997 Cobbley et al.
5617148 April 1, 1997 Montgomery

Foreign Patent Documents

58482 August 1982 EPX
372 601 June 1990 EPX
411 232 February 1991 EPX
441 702 August 1991 EPX
493 091 July 1992 EPX
551 016 A1 July 1993 EPX
581 317 February 1994 EPX
605 208 A2 July 1994 EPX
629 972 December 1994 EPX
650 146 A1 April 1995 EPX
649 074 A1 April 1995 EPX
705 025 A2 April 1996 EPX
3806411 September 1989 DEX
4-248771 September 1992 JPX
5-242217 September 1993 JPX
2063018 May 1981 GBX
2067871 July 1981 GBX
2196167 April 1988 GBX
2204984 November 1988 GBX
WO 89/08915 September 1989 WOX
WO95/10835 April 1995 WOX
WO 95/20291 July 1995 WOX
WO 9626494 August 1996 WOX
WO 9627259 September 1996 WOX
WO 9325038 December 1996 WOX

Other references

  • Tirkel et al, "Electronic Water Mark," DICTA-93, Macquarie University, Sydney, Australia, Dec., 1993, pp. 666-673. Koch et al., "Copyright Protection for Multimedia Data," Fraunhofer Institute for Computer Graphics, Dec. 16, 1994, 15 pages. "Access Control and COpyright Protection for Images, WorkPackage 8: Watermarking," Jun. 30, 1995, 46 pages. "Access Control and Copyright Protection for Images, WorkPackage 3: Evaluation of Existing Systems," Apr. 19, 1995, 68 pages. Boneh, "Collusion-Secure Fingerprinting for Digital Data," Department of Computer Science, Princeton University, 1995, 31 pages. Friedman, "The Trustworthy Digital Camera: Restoring Credibility to the Photographic Image," IEEE Transactions on Consumer Electronics, vol. 39, No. 4, Nov., 1993, pp. 905-910. "Cyphertech Systems: Introduces Digital Encoding Device to Prevent TV Piracy," Hollywood Reporter, Oct. 20, 1993, p. 23. "NAB--Cyphertech Starts Anti-Piracy Broadcast Tests," Newsbytes, NEW03230023, Mar. 23, 1994. Humphrey, "Stamping Out Crime," Hollywood Reporter, Jan. 26, 1994, p. S48. "Copyright Protection for Digital Images, Digital Fingerprinting from FBI," Highwater FBI brochure, 1995, 4 pages. "Access Control and COpyright Protection for Images, Conditional Access and Copyright Protection Based on the Use of Trusted Third Parties," 1995, 43 pages. Caronni, "Assuring Ownership Rights for Digital Images," Published in the Proceedings of `Reliable IT Systems,` VIS '95, HH. Bruggemann and W. Gerhardt-Hackl (Ed.), Vieweg Publishing Company, Germany, 1995, Jun. 14, 1994, 10 pages. Choudhury, et al., "Copyright Protection for Electronic Publishing over Computer Networks," IEEE Network Magazine, Jun. 1994, 18 pages. Moller, et al., "Rechnergestutzte Steganographie: Wie sie Funktioniert und warum folglich jede Reglementierung von Verschlusselung unsinnig ist," DuD, Datenschutz und Datensicherung, 18/6 (1994) 318-326. Pennebaker et al., JPEG Still Image Data Compression Standard, Chapter 3, "Aspects of the Human Visual System," pp. 23-27, 1993, Van Nostrand Reinhold, New York. Castro et al., "Registration of Translated and Rotated Images Using Finite Fourier Transforms," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. PAMI-9, No. 5, Sep. 1987, pp. 700-703. Weber et al., "Correlative Image Registration," Seminars in Nuclear Medicine, vol XXIV, No. 4, Oct., 1994, pp. 311-323. Toga et al., "Registration Revisited," Journal of Neuroscience Methods, 48 (1993), pp. 1-13. Sheng et al., "Experiments on Pattern Recognition Using Invariant Fourier-Mellin Descriptors," Journal of Optical Society of America, vol. 3, No. 6, Jun., 1986, pp. 771-776. Kurak et al., "A Cautionary Note On Image Downgrading," 1992, IEEE, pp. 153-159. Wagner, "Fingerprinting," 1983 IEEE, pp. 18-22. Nakamura et al., "A Unified Coding Method of Image and Text Data Using Discrete Orthogonal Transform," Systems and Computers in Japan, vol. 21, No. 3, 1990, pp. 87-92. Simmons, "Subliminal Channels; Past and Present," ETT, vol. 5, No. 4, Jul.-Aug. 1994, pp. 45-59. Nakamura et al., "A Unified Coding Method of Dithered Image and Text Data Using Micropatterns," Electronics and Communications in Japan, Part 1, vol. 72, No. 4, 1989, pp. 50-56. Tanaka, "Embedding the Attribute Information Into a Dithered Image," Systems and Computers in Japan, vol. 21, No. 7, 1990, pp. 43-50. Short, "Steps Toward Unmasking Secure Communications," International Journal of Bifurcation and Chaos, vol. 4, No. 4, 1994, pp. 959-977. Schreiber et al., "A Compatible High-Definition Television System Using the Noise-Margin Method of Hiding Enhancement Information," SMPTE Journal, Dec. 1989, pp. 873-879. Tanaka et al., "New Integrated Coding Schemes for Computer-Aided Facsimile," Proc. IEEE Int'l Conf. on Sys. Integration, Apr. 1990, pp. 275-281. Tanaka et al., "Embedding Secret Information Into a Dithered Multi-Level Image," Proc. IEEE Military Comm. Conf., Sept. 1990, pp. 216-220. Matsui et al., "Video-Steganography: How to Secretly Embed a Signature in a Picture," IMA Intellectual Property Project Proceedings, Jan. 1994, vol. 1, Issue 1, pp. 187-205. van Schyndel et al., "A Digital Watermark," IEEE International Conference on Image Processing, Nov. 13-16, 1994, pp. 86-90. Fitzgerald, "Invisible Digital Copyright ID," Editor & Publisher, Jun. 25, 1994, p. 62. "Foiling Card Forgers With Magnetic `Noise,`" Wall Street Journal, Feb. 8, 1994. Jain, "Image Coding Via a Nearest Neighbors Image Model," IEEE Transactions on Communications, vol. COM-23, No. 3, Mar. 1975, pp. 318-331. Arthur, "Digital Fingerprints Protect Artwork," New Scientist, Nov. 12, 1994, p. 24. Matthews, "When Seeing is Not Believing," New Scientist, Oct. 16, 1993, pp. 13-15. Bender et al., "Techniques for Data Hiding," Massachusetts Institute of Technology, Media Laboratory, Jan. 1995, 10 pages. Komatsu et al., "Authentication System Using Concealed Image in Telematics," Memoirs of the School of Science & Engineering, Waseda Univ., No. 52, 1988, pp. 45-60. Walton, "Image Authentication for a Slippery New Age," Dr. Dobb's Journal, Apr. 1995, pp. 18-26, 82-87. Port, "Halting Highway Robbery on the Internet," Business Week, Oct. 17, 1994, p. 212. Komatsu et al., "A Proposal on Digital Watermark in Document Image Communication and Its Application to Realizing a Signature," Electronics and Communications in Japan, Part 1, vol. 73, No. 5, 1990, pp. 22-33. Machado, "Announcing Stego 1.0a2, The First Steganography Tool for the Macintosh," Internet reference, Nov. 28, 1993, 3 pages. Brown, "S-Tools for Windows, Version 1.00, .COPYRGT.1994 Andy Brown, What is Steganography," Internet reference, Mar. 6, 1994, 6 pages. shaggy@phantom.com, "Hide and Seek v. 4.0," Internet reference, Apr. 10, 1994, 3 pages. Arachelian, "White Noise Storm," Apr. 11, 1994, Internet reference, 13 pages. Schneier, "Digital Signatures, Cryptographic Algorithms Can Create Nonforgeable Signatures for Electronic Documents, Making Them Valid Legal Instruments" BYTE, Nov. 1993, pp. 309-312. Wise, "The History of Copyright, Photographers' Rights Span Three Centuries," PHOTO>Electronic Imaging, vol. 37, No. 6, 1994. Kassam, Signal Detection in Non-Gaussian Noise, Dowden & Culver, 1988, pp. 1-96. Brassil et al., Electronic Marking and Identification Techniques to Discourage Document Copying, Proceedings of INFOCOM '94 Conference on Computer, IEEE Commun. Soc Conference, Jun. 12-16, 1994, pp. 1278-1287. Sapwater et al., "Electronic Copyright Protection," PHOTO>Electronic Imaging, vol. 37, No. 6, 1994, pp. 16-21. Hecht, "Embedded Data Glyph Technology for Hardcopy Digital Documents," SPIE vol 2171, Feb. 1994, pp. 341-352. Roberts, "Picture Coding Using Pseudorandom Noise," IRE Trans. on Information Theory, vol. 8, No. 2, Feb., 1962, pp. 145-154. Bruyndonckx et al., "Spatial Method for Copyright Labeling of Digital Images," 1994, 6 pages. Gabor, et al., "Theory of Communication," J. Inst. Elect. Eng. 93, 1946, pp. 429-441. Bruyndonckx et al., Neural Network Post-Processing of Coded Images Using Perceptual Masking, 1994, 3 pages. Pickholtz et al., "Theory of Spread-Spectrum Communications--A Tutorial," Transactions on Communications, vol. COM-30, No. 5, May, 1982, pp. 855-884. Sklar, "A Structured Overview of Digital Communications--a Tutorial Review--Part I," IEEE Communications Magazine, Aug., 1983, pp. 1-17. Sklar, "A Structured Overview of Digital Communications--a Tutorial Review--Part II," IEEE Communications Magazine, Oct., 1983, pp. 6-21. Tirkel et al., "A Two-Dimensional Digital Watermark," 1995, 6 pages. Delaigle et al., "A Psychovisual Approach for Digital Picture Watermarking," 1995, 20 pages. Rindfrey, "Towards an Equitable System for Access Control and Copyright Protection in Broadcast Image Services: The Equicrypt Approach," Intellectual Property Rights and New Technologies, Proc. of the Conference, R. Oldenbourg Verlag Wien Munchen 1995, 12 pages. Sandford II, et al., "The Data Embedding Method," SPIE vol. 2615, Oct. 23, 1995, pp. 226-259. Tanaka et al., "A Visual Retrieval System with Private Information for Image Database," Proceeding International Conference on DSP Applications and Technology, Oct. 1991, pp. 415-421. JPEG Group's JPEG Software (release 4), FTP.CSUA.BEREKELEY.EDU /PUB/CYPHERPUNKS/APPLICATIONS/ JSTEG/JPEG.ANNOUNCEMENT.GZ, Jun. 7, 1993, 2 pages. Dautzenberg, "Watermarking Images," Department of Microelectronics and Electrical Engineering, Trinity College Dublin, 47 pages, Oct. 1994. Arazi, et al., "Intuition, Perception, and Secure Communication," IEEE Transactionson Systems, Man, and Cybernetics, vol. 19, No. 5, Sep./Oct. 1989, pp. 1016-1020.

Patent History

Patent number: 5748783
Type: Grant
Filed: May 8, 1995
Date of Patent: May 5, 1998
Assignee: Digimarc Corporation (Portland, OR)
Inventor: Geoffrey B. Rhoads (West Linn, OR)
Primary Examiner: Leo Boudreau
Assistant Examiner: Brian P. Werner
Law Firm: Klarquist Sparkman Campbell Leigh & Whinston
Application Number: 8/436,102